earth online

ALGOM

Overview

The ALGOM: GOMOS Level 2 Algorithm Evolution Studies project consists of different Level 2 studies, the objective is to improve the quality of GOMOS products. The work is performed in the framework of the GOMOS Quality Working Group, whose responsibility is to advise on the operations performance of a mission's instruments and its products, as well as on the evolution of algorithms, calibration, validation and processors.

Envisat's Earth observation instrument, GOMOS (Global Ozone Monitoring by Occultation of Stars), is a spectrometer that exploits the stellar occultation technique. GOMOS comprises of one UV-Visible channel (248-690 nm) and two near infrared channels (756-773 nm and 926-952 nm). These wavelength regions allow retrieving atmospheric vertical profiles of O3, NO2, NO3, O2, H2O, atmospheric density and aerosols.

ALGOM is an Instrument Characterisation and Algorithm Study. Maintenance and improvements of instrument characterisation and algorithm definition are crucial activities to guarantee that the requirements formulated in the Mission Requirement Document. These activities are nominally managed within the Quality Working Group (QWG), though some complementary studies are funded by ESA for supporting ad-hoc recalibration and reprocessing campaigns as well as for developing advanced scientific processors and innovative geophysical products.

Contact Information

If you have any questions about this project, contact:

Angelika Dehn
Email: angelika.dehn@esa.int
Organisation: ESA/ESRIN

Janne Hakkarainen
Email: janne.hakkarainen@fmi.fi
Organisation: Finnish Meteorological Institute

Data

The ALGOM GOMOS datasets are available below. Technical notes describing the results of the works can be found in the ALGOM Project Documentation section.


ALGOM 2s v1.0 O3 Profiles - Two-Step Approach

A new algorithm for GOMOS O3 data in the UTLS has been developed within the framework of the ESA ALGOM project. ALGOM 2s v1.0 O3 Profiles using Two-Step Approach dataset can be downloaded here.

The O3data from 10 km to 105 km are stored in NetCDF-4 format, on 1 km grid. The data is available in monthly data files. The new dataset covers the period from August 2002 up to December 2011.

Download Two-Step Dataset

 

More detailed information relating to this dataset is available in the following dedicated Data Release Documentation:


ALGOM1s v1.02 Profiles - One-Step Approach

A new algorithm for GOMOS O3 data in the UTLS has been developed within the framework of the ESA ALGOM project. GOMOS ALGOM1s v1.02 O3 Profiles using One-Step Approach dataset can be downloaded here.

The O3 data are given in NetCDF-4 files (one file per occultation) and covers the period from 29 April 2002 up to 08 April 2012.
 

Download One Step Dataset 2002-2006
Download One Step Dataset 2007-2012

 

More detailed information relating to this dataset is available in the following dedicated Data Release Documentation:


ALGOM Level 1c Products of averaged spectra for minor species retrivial

GOMOS averaged transmittances spectra have been built within the framework of the ESA ALGOM project. GOMOS ALGOM Level 1c Products dataset can be downloaded here.

The dataset covers the period from April 2002 up to December 2005.

Download Level 1c Products Dataset

 

More detailed information relating to this dataset is available in the following dedicated Data Release Documentation:

Activity Consortium

ACRI Group logo

ACRI Group
            
Finnish Meteorological Institute logo

Finnish Meteorological Institute

 

Royal Belgian Institute for Space Aeronomy logo


Royal Belgian Institute for Space Aeronomy
            
LATMOS logo

Laboratoire Atmosphères, Milieux, Observations Spatiales
(Atmospheres Laboratory, Backgrounds, Space Observations)
Tweet